Planar and axial channeling of 800-keV As in 〈110〉 silicon

Abstract

We believe that we have observed planar channeling of As in the open {112} plane of Si by measurement of the depth distribution of electrically active As implanted in Si at 800 keV. The assumed planar‐channeled distribution is sharply peaked and is found for ions directed 0.55 ° away from the 〈110〉 axis in the direction of the {112} plane. This distribution occurs 2.6 μm in depth with a FWHM of only 800 Å and contains 3% of the total 1.5×10¹² cm⁻² implanted As ions. The corresponding sharply peaked 〈110〉 axial‐channeled As distribution occurs 5.5 μm in depth with a FWHM of 0.40 μm and contains 28% of the implanted As ions. The axial‐channeling distribution degrades as the angle away from the 〈110〉 axis increases until at 0.55° the planar‐channeling distribution occurs abruptly and the axial‐channeling distribution nearly disappears. The electronic stopping power of Si for 800‐keV As ions in the {112} plane is determined to be 1.05×10⁻¹³ cm² eV from these data and from accurately channeled (by Rutherford backscattering) As ion ranges measured in Si from 10 to 800 keV. While the axial‐channeled distribution is skewed toward the surface, the planar‐channeled distribution does not appear to be skewed.